The present invention relates to a fitting for receptacles such as tank cars or containers comprising a housing, having an inlet opening and an outlet opening, and a rotatable body with a through passageway, having an inflow opening and an outflow or discharge opening, in which the rotatable body is rotatably arranged in the housing such that in an open position it provides communication between the inlet opening and the outlet opening, and in a closed position is blocks communication between the inlet opening and the outlet opening.
A fitting of this type, whose rotating body is constructed essentially as spherical and which is positioned in the region of an opening in the bottom of the receptacle of a tank vehicle, is known from U.S. Pat. No. 3,286,735. A shaft is coupled to the spherical rotating body, which, after the installation of the fitting in the receptacle, is located therein, the fitting having a relatively large height. Seat rings, which press against the spherical external surface of the rotating body and are fixed in the housing using adjustable annular sleeves, are provided in the region of the inlet openings for sealing. To preset and/or set the sealing force of the seat rings, the sleeves described are rotatably mounted in the housing via threaded connections, the sleeves described being moved independently of one another from both sides in relation to the rotating body in opposite directions to elevate the sealing force. After the installation of the fitting in the receptacle, the setting may be performed in the inside of the receptacle, or the fitting must be uninstalled from the receptacle.
Furthermore, a fitting is known, from U.S. Pat. No. 4,518,149, whose rotating body is constructed as a plug and is mounted rotatably around an essentially horizontal rotational axis and in the housing using a bushing made of plastic, particularly polytetrafluoroethylene, the seal in relation to the housing furthermore resulting from using the bushing. In a first embodiment, the fitting is constructed as a plug cock whose housing has an essentially vertically arranged passage having an inlet opening and an outlet opening. The plug has a through hole having an inflow opening and an outflow opening, which, in the open position, align with the inlet opening and the outlet opening of the housing. The cross-section of the through hole of the plug and the outlet opening of the housing are smaller than the cross-section of a connection branch for a line or a hose for loading or filling. As a consequence of the reduction in cross-section described, relatively long times must be accepted for loading and unloading and/or for filling or emptying the tank receptacle. It is noted here that, during unloading or emptying, the fluid or the medium stored in the receptacle flows in through the inlet opening of the housing and the inflow opening of the rotating body and flows out through the outflow opening of the rotating body and the outlet opening of the housing. In contrast, the flow direction is reversed in the case of loading or filling, so that the medium or fluid flows in through the outlet opening and the outflow opening and reaches the receptacle through the inflow opening of the rotating body and the inlet opening of the housing. Furthermore, the plug contains a small lateral opening, which is located in the region of the internal bottom surface of the receptacle in the open position, in order to allow it to be completely emptied. The rate of flow is, however, not influenced by this small opening. By enlarging the diameter of the plug, the shortcoming caused by the reduction in cross-section may be counteracted, however, in this way the overall volume and particularly the overall height of the fitting is enlarged disadvantageously.
In a further embodiment, the rotating body is constructed as a sphere having a through-hole with a correspondingly enlarged cross-section. The overall volume and, above all, the overall height, in the vertical direction and/or in the direction of the through opening of the housing, are, however, considerable in this embodiment. Furthermore, significant expense is associated with the setting and/or the adjustment of the test pressure of sealing elements, and consequently the sealing force on the spherical rotating body, in the mounted state of the fitting, since these measures must be carried out inside the tank.
It is an object of the invention to provide an improved fitting of the aforementioned type.
A further object of the invention is to provide a fitting that can be constructed at reasonable cost.
Another object of the invention is to provide a fitting with a small overall volume and/or overall height in which the sealing force of the seat rings may be easily set.
It is also an object of the invention to provide a fitting in which only a low operating torque is necessary for rotating the rotating body.
These and other objects are achieved in accordance with the present invention by providing a fitting for a fluid receptacle, said fitting comprising a housing having two inlet openings and an outlet opening, and a rotatable body rotatably disposed in said housing, said rotatable body having a through passage with two inflow openings and an outflow opening, and said rotatable body when rotated into an open position, communicating the inlet openings with the outlet opening, and when in a closed position, blocking communication between the inlet openings and the outlet opening; said two inflow openings having cross-sections which are at least approximately equally large, and said housing having a bearing ring in the vicinity of the second inflow opening or a seat ring in the vicinity of the second inlet opening; wherein said rotatable body is constructed as a plug having a conical outer surface, and a predetermined small annular gap exists between the plug outer surface and an associated conical inner surface of a hole in the housing in which the plug is inserted; said housing having a seat ring in the vicinity of the outlet opening, against which seat ring the conical outer surface of the rotating body presses against to form a seal; wherein an axial adjustment of the rotatable body and consequent adjustment of the sealing pressure of the seat ring is controlled by adjustment of a clamping ring after the fitting is installed in the receptacle, and wherein the adjustment of the clamping ring is performable outside of the receptacle.
The fitting according to the present invention, which particularly may be constructed as a plug cock, is distinguished by simple and nonetheless reliable construction and, in the open position of the rotating body, ensures a large flow rate of the medium and therefore short loading times and/or unloading times. The cross-sections of the openings of the housing and the rotating body described are selected and tailored to the cross-section of the connection flange in such a way that, during loading and unloading, there is unhindered free flow of the medium or fluid, without a disadvantageous reduction of cross-section. The rotating body contains a second inflow opening having a comparatively large cross-section, through which a significant proportion of the medium flowing through the rotating body flows in the open position of the rotating body. The cross-section of the second inflow opening is essentially at least as large as the cross-section of the first inflow opening. Furthermore, the cross-section of the outlet opening of the housing is advantageously at least approximately as large as the cross-section of the opening of the connection flange. Furthermore, the housing contains a bearing ring or sealing ring which, at least in the open position of the rotating body, is essentially coaxial to the second inflow opening described.
In a separate embodiment, the housing contains, in the vicinity of the outflow opening of the rotating body, on the outflow side, and/or toward the outside of the receptacle, a seat ring and/or a sealing ring, due to which a lower operating torque and/or a lower torque for rotating the body during opening or closing is ensured. This is particularly true in comparison to a plug cock, whose plug is mounted so it rotates and forms a seal in a bushing of the housing. In a further embodiment, both inflow openings of the rotating body are positioned diametrically opposed and preferably coaxial to one another, like both of the assigned inlet openings of the housing, the respective cross-sections of the openings being essentially equally large. In this case, the axes of the openings described are essentially orthogonal to the rotational axis of the rotating body, preferably constructed as a plug, each of the two inlet openings of the rotating body being assigned a seat ring positioned in the housing.
In all embodiments of the fitting according to the present invention, the sealing forces of the seat rings and the sealing elements are set in the region of the outside of the receptacle, so that in the mounted state of the fitting, setting or adjustment may be performed at any time as necessary, without anything further.
To satisfy safety requirements, a lever for operating the rotating body and/or a flange positioned on the outflow side and/or in the region of the outside of the receptacle or similar, is provided with predetermined breaking points, so that in case of a possible accident, the fitting remains undamaged and therefore fully functional and sealed. The fitting according to the present invention allows direct and safe mounting and operation directly in the receptacle. Furthermore, the fitting is distinguished by high cost effectiveness, since comparatively few components are necessary. Furthermore, low installation height is of particular significance, a high flow rate of the medium with which the receptacle is to be filled or which is to be emptied from the receptacle nonetheless being ensured. Furthermore, by using standardized components, high requirements for quality and functional reliability are fulfilled. The fitting is preferably integrated into a manhole cover and may be connected easily to the receptacle, particularly by welding.